#!/usr/bin/env sh
# Generate compile_commands.json for clangd.
#
# Uses bear when available so every real compile command is captured
# (future-proof as the project grows). Otherwise hand-rolls the single
# entry from the flags in the generated Makefile — one source file, one
# entry, no mysteries.
set -eu

ROOT=$(cd "$(dirname "$0")/.." && pwd)
cd "$ROOT"

if [ ! -f Makefile ]; then
    echo "gen-compile-commands: no Makefile found - run ./autogen.sh first" >&2
    exit 1
fi

if command -v bear >/dev/null 2>&1; then
    bear -- make -B >/dev/null
    # Drop the configure probes (conftest.c); clangd only wants real files.
    jq 'map(select(.file | endswith("conftest.c") | not))' compile_commands.json \
        > compile_commands.json.tmp && mv compile_commands.json.tmp compile_commands.json
    echo "compile_commands.json generated via bear"
    exit 0
fi

CC=$(sed -n 's/^CC = //p' Makefile | head -n1)
[ -z "$CC" ] && CC=cc
DEFS=$(sed -n 's/^DEFS = //p' Makefile | head -n1)
AM_CFLAGS=$(sed -n 's/^AM_CFLAGS = //p' Makefile | head -n1)
CFLAGS=$(sed -n 's/^CFLAGS = //p' Makefile | head -n1)

# Drop defines carrying embedded quotes (PACKAGE_* metadata): they would
# break JSON and clangd does not need them.
SAFE_DEFS=''
for d in $DEFS; do
    case "$d" in
        *\"*) ;;
        *) SAFE_DEFS="$SAFE_DEFS $d" ;;
    esac
done

CMD="$CC$SAFE_DEFS -I. $AM_CFLAGS $CFLAGS -c src/main.c -o src/main.o"

if command -v jq >/dev/null 2>&1; then
    jq -n --arg d "$ROOT" --arg c "$CMD" --arg f "$ROOT/src/main.c" \
        '[{directory: $d, command: $c, file: $f}]' > compile_commands.json
else
    printf '[{"directory":"%s","command":"%s","file":"%s"}]\n' \
        "$ROOT" "$CMD" "$ROOT/src/main.c" > compile_commands.json
fi
echo "compile_commands.json generated (fallback)"